As of March 2013, it consists of three matrilines and 15 members and is the family of Springer, the first orca to be successfully reintroduced to the wild after being handled by humans.
Also, when the study began, it was assumed that orca pods were harems led by mature males.
Starting in the early 2000s, Yakat's oldest daughter Skagit (A35) and her offspring began spending time apart from the rest of the group, thus creating a third matriline, A35.
In 2002, Springer was found alone and emaciated in Puget Sound, several hundreds of miles away from her family's home range.
After being taken to Johnstone Strait and brought back to health, she was successfully reintroduced to wild whales before settling in with her grand aunt Yakat's matriline.
In 2006, Yakat's son Skeena (A13) sustained an injury to the top of his dorsal fin and her great-grandchild Canoona (A82) was hit by a boat propeller.
Having four reproductive females, A4 pod can be recognized by its large proportion of young calves and juveniles.